1. Technical Field
A method for inhibiting pattern width slimming or reduction of photoresists is disclosed. In particular, a method for inhibiting pattern width slimming due to the beam emitted by a scanning electron microscope (hereinafter, it is abbreviated to xe2x80x9cSEMxe2x80x9d) while measuring a critical dimension (hereinafter, it is abbreviated to xe2x80x9cCDxe2x80x9d) of a photoresist pattern obtained by using a photoresist composition comprising thermal acid generator is disclosed.
2. Description of the Prior Art
Typically, the semiconductor processing is carried out by setting up a CD target and the SEM measures the CD when a photoresist pattern is formed. When the CD is measured immediately after a pattern is formed, the CD is almost identical with a target. However, thirty seconds after the CD measurement by the SEM, that is, during the observation by the SEM, width of the pattern gets slimmed. The basic mechanism of the SEM is that image is seen through e-beam projected under high vacuum. Most of the ArF photoresist gets cracked due to e-beam and at that time, the cracked parts are disappeared due to high vacuum, which consequently slims pattern width. Therefore, there were many problems in establishing the CD target during a semiconductor processing because measuring the CD itself is very difficult.
A method for preventing a photoresist pattern from being slimming while measuring its CD using SEM is disclosed by forming the photoresist pattern using a photoresist composition containing a thermal acid generator and additionally heating the formed photoresist pattern after developing step.